How much does it cost to fix boiler error code b2, b3, b4, b5,b6?

Typical repair cost for the boiler b2, b3, b4, b5,b6 fault is £250-£550 including labour.

b2, b3, b4, b5,b6 High

Boiler Fault Code b2, b3, b4, b5,b6

Also written as B2B3B4B5B6 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code b2, b3, b4, b5,b6 appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's internal computer has encountered a data corruption or communication error, preventing the system from running safely. (As reported on Worcester Bosch Greenstar 25 HE Combi)

Pick your boiler brand for the b2, b3, b4, b5,b6 fix

Worcester Bosch b2, b3, b4, b5,b6 2 models

Source

Information for the b2, b3, b4, b5,b6 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026